From the Workbench
Hardware tinkering, test equipment repairs, and builds that involve soldering irons, oscilloscopes, and occasionally voiding warranties.
The RAMSA Meter Bridge
A 390-LED meter bridge from Panasonic’s 1998 RAMSA WR-DA7 digital mixing console, brought back to life as a spectrum analyzer for whatever the PC is playing. There is no console and no published description of how the two talk, and the case was never opened: everything goes in through the connector on the back, driven from an Arduino Nano and a cheap USB-serial adapter.
Read more →The Alesis ADAT RMB
A 32-channel Remote Meter Bridge for the original Alesis ADAT. The connector topology and every DB9 pin are documented; the meter-data encoding remains open. The project tracks confirmed facts, testable hypotheses, all decay and peak-control behavior, and the bench work needed for a safe four-port source.
Read the findings →
RF Bench Analyser
A spectrum analyser front panel for the whole bench. It began with a Rohde & Schwarz CMU200 or CRTU and now drives fourteen kinds of instrument, a tinySA, an oscilloscope, a NanoVNA and a rack of SDRs among them: seven traces, eight markers, fourteen measurement windows, a network analyser, a transmitter and receiver test bench, level calibration, and scripting in C# or Python.
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ShackLink Knob
A ShackLink client you hold in one hand. A round 360×360 touch screen and a real tuning knob show the radio’s frequency, the SDR’s live spectrum and waterfall, the band and mode, and the server’s 48 shared memories, with the station’s audio in a pair of headphones. Firmware for the Waveshare ESP32-S3 1.8″ Knob, talking to the ShackLink server over WiFi.
Read more →What’s Next
Current project in the pipeline: a 130ft end-fed half-wave antenna using a tall pine tree and drone-assisted wire deployment. Check the home page for the latest updates.